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astrophysics

cosmology

Why the Big Bang’s Light May Have a Tilt

Scientists haven’t tested the Big Bang’s light for a revealing shift in 25 years. A new experiment aims to change that.

astrophysics

The Particle That Broke a Cosmic Speed Limit

Physicists are beginning to unravel the mysteries of ultrahigh-energy cosmic rays, particles accelerated by the most powerful forces in the universe.

astrophysics

Strange Stars Pulse to the Golden Mean

Nature has revealed peculiar mathematical objects that connect order and chaos.

cosmology

Joint Dust Analysis Deflates Big Bang Signal

No definitive evidence for cosmic inflation is found, but support remains strong for the theory even as critics highlight its shortcomings as an explanation for how and why the universe began.

astrophysics

Dwarf Galaxies Dim Hopes of Dark Matter

For five years physicists have been tantalized by possible evidence of dark matter in the Milky Way’s center. But new results from small satellite galaxies have complicated the story.

BICEP2 graphic.
cosmology

‘Big Bang Signal’ Could All Be Dust

Cosmic dust in the high latitudes of the Milky Way could account for the entire swirl pattern that had been presented as proof of a leading Big Bang theory, according to a new data analysis from the Planck satellite.

Blanco telescope.
Q&A

Finding Dark Energy in the Details

The astrophysicist Joshua Frieman seeks to pinpoint the mysterious substance driving the accelerating expansion of the universe.

Katherine Freese
Q&A

In Search of Dark Stars

Katherine Freese, a physicist who will soon lead the Nordic Institute for Theoretical Physics, reflects on the hunt for dark matter and how dark matter heating may have produced the first stars.

Gamma Ray Excess
astrophysics

Case for Dark Matter Signal Strengthens

A new analysis strengthens the case that gamma rays emanating from the center of the Milky Way come from dark matter particles known as WIMPs.